Bob-sled



(No Model.)

J. s. WILLSON & W.-H. MACK.

BOB SLED.

N0. 349,378. Patented Sept. 21, 1886.

UM10 7 8 I WWW 7W 77 Marita 8 UNITED STATES PATENT OFFICE.

JOHN S. WVILLSON AND WILLIAM H. MACK, OF MILWAUKEE, WISCONSIN.

BOB-SLED.

SPECIFICATION forming part of Letters Patent No. 349,378, dated September 21, 1886.

Application filed October 5, 1885. Serial No. 178,979. (No model.)

To all whom it may concern.-

Be it known that we, JOHN S. WILLSON and WILLIAM H. liIAOK, of Milwaukee, in the county of Milwaukee and State of \Visconsin, have invented new and useful Improvements in Bob-Sleds; and we do hereby declare the following to be a full, clear, and exact description of saidinvention, reference being had to the accompanying drawings, and to the lettens or figures of reference marked thereon, which form a part of this specification.

Our invention, to be hereinafter claimed, relates to improvements in bob sleds or sleighs that are connected together in pairs, and in which the front sled is rigidly connected to the bolster of the rear sled, and the nose of the rear sled is connected to the front sled by a pivoted or jointed tongue.

Our invention relates particularly to the con struction, form, and location of parts,whereby a variation of relative distances between parts of two sleds is permitted when the sleds pass over irregularities of surface, and a minimum of strain on the sled and connecting parts is secured.

We are aware of the United States Patent No. 171,271, issued December 21, 1875, to Francis Dillon, for improvements in bob-sleds, and

. Patent N o. 243, 992, issued July 5, 1881, to Herbert L. Steele, for improvements in sleigh-bolsters, and do not claim the devices therein shown and described.

In the accompanying drawings, Figure 1 is a side elevation of a pair of sleds, showing our improvement on the rear sled, a feature of its operation being indicated by dotted'lincs. Fig. 2 is a rear View of the device embodying our invention, a part being in section to show other parts more fully. Fig. 3 is a detail. Fig. 4 is a modified form of the device shown in Fig. 2.

The same letters refer to like parts in all the views.

The two sleds A A have each runners Z) Z), knees c 0, and a cross-beam, (Z, rigid upon and connecting the two knees of each sled together, in the manner common in all sleds. The sleds are each provided with a bolster, 6, above, parallel to, and supported upon the beam (Z. The two bolsters are usually connected rigidly together by a reach, f, or a box, 9, or a rack or load of logs or lumber, or equivalent means,

and it is with reference to such rigid connection of the two bolsters that our device is provided. The rear sled, A, is also connected to the forward sled, A, by a tongue, h, attached to the rear sled by and through a movable roller, 2', in the nose of the runners Z), and attached to the front sled by and through the bolster or beam in a movable joint, 7', the bolster on the front sled being attached by a central king-bolt to the beam of the sled. The bolster over the beam of the rear sled is made considerably wider from front to rear than is usual for bolsters, and is provided on its under side with two or more rigid downwardlyp roj ectin g brackets, is, turned inwardly at their lower edge, forming a groove from front to rear on the under side of the bolster. Preferably, there are two of these brackets on each bolster, one near each end over or nearly over the knees of the sled. 7

On the beam d of the rear sled, and rigidly affixed thereto, are two or more supportinglegs, Z, provided with a side projecting pin, m, which pin is adapted to enter and move forward and backward in the groove in bracket 70, the legs Z being located on the beam directly beneath the foot of the bracket k, so that the bolster is supported by and through the brackets k in resting (and movable front and rear) on the legs Z Z. The grooves in the two brackets k k are turned in opposite directions, and the 'pins on the legs Z Z are accordingly so turned as to enter the grooves in said brackets, and the boslter is thereby retained (movably front and rear) onthe beam of the sled.

In Fig. 4 a modified form of the leg Z is shown, in which an anti-friction roller, a, is inserted in the top of the leg for the support and easy movement of the bolster thereon. That the bolster 6' may not slide off its bearings, we preferably close up the front and rear ends of the groove in bracket is, as shown in Fig. 1. It will be seen that, the bobs being connected together by a tongue, h, and the bolsters being connected by a reach, f, or equivalent means, when the rear bob goes into a depression in the ground 0 the front end of the runners will first go down, and as the nose is held firmly to the beam of the front sled by the tongue h, and at a constant radial distance there- IOO from,and the two bolsters are held at a constant distance apart by thereacl1f,tl1at while the run 11ers of the rear sled tip down at the front, the knees and beam, as they are rigid to the runners, will swing forward, and the relative distance of rear bolster, c, and the rear beam to the front bolster and beam will change, the rear beam sliding forward in. relation. to the bolster thereon, which motion will be reversed as the rear sled comes again upon the plane with the front sled. Similar variations of relative distances in the parts occur when the sleds pass over elevations, as when going into and out of depressions, but in reverse order; and it will be observed that as the legs I, which are rigid to the beam 11, move forward and back as the front end of the rear bob tips down and up, the point of support of the rear end of the load or box is changed from the front to the rear of the under side of the bolster 0, thereby correspondingly shifting on the runner of the sled the point of the vertical weight of the load, whereby, as will also be understood, as the front end of the bob is elevated in rising a hummoelc the weight on the rear sled will be carried farther to the rear on the runner, and as the point of contact of the legs I with the bolster o is moved farther away from the front supportingbolster, o, more of the weight of 0 theload will be thrown on the front bolster,

and as the result of this change in the distribution or location of the weight the strain upon the sled is reduced to its minimum, and the rear bob passes over the hammock with greater case than when connected and oper ating in the method heretofore in use.

XV hat we claim as new, and desire to secure by Letters Patent, is-

1. In sleds, the beam (Z and two or more legs, 11, rigid on said beam, said legs being each provided with a pin, m, in combination with bolster o and bracket 7r, rigid on the under side of said bolster, said bracket being provided with a groove adapted to receive and ,permit of the free sliding movement therein 

